Impeller

ABSTRACT

An impeller in embodiments, as an example, includes a base plate, and a shroud including a plurality of blade members fixed to the base plate, wherein a plurality of the blade members are provided so as to stand and are arranged with intervals in a circumferential direction on a face portion of the shroud, the face portion facing the base plate, a plurality of groove portions for mounting each of a plurality of the blade members are formed on the base plate, and a plurality of the groove portions are configured to mount each of the blade members included in a plurality of kinds of the shrouds in which at least one of an arrangement of the blade members and a number of the blade members is different from each other.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is entitled under 35 U.S.C. § 119 to the benefit of Japanese Patent Application No. 2018-7405, filed on Jan. 19, 2018.

TECHNICAL FIELD

The present disclosure relates to an impeller.

BACKGROUND DISCUSSION

For example, an impeller installed in an electric pump is disclosed (for example, JP 2016-23635A). In the electric pump, the impeller is mounted on a rotor included in a motor unit. Specifically, the impeller is configured such that end portions of a plurality of blade members included in a shroud are mounted in groove portions formed on one end face (a base plate) of he rotor.

In such an electric pump, however, impellers in which an arrangement of blade members and the number of the blade members are different from each other depending on intended use may be used. Herein, the arrangement of the blade members means a circumferential-direction layout of a plurality of blade members to be mounted on a base plate. The arrangement of the blade members differs depending on an inclination direction and inclination degree of the blade members when a straight line extending radially from the center of the base plate is defined as a reference. Usually, groove portions for use in mounting the blade members on one end face (the base plate) of a rotor are associated with the blade members of a shroud to be mounted. For this reason, in order to install, in the electric pump, the impellers in which an arrangement of the blade members and the number of the blade members are different from each other, it is necessary to individually prepare a rotor in which groove portions for mounting the blade members are formed on one end face (the base plate).

A need thus exists for an impeller which is not susceptible to the drawback mentioned above.

SUMMARY

An impeller in embodiments, as an example, includes a base plate, and a shroud including a plurality of blade members fixed to the base plate. A plurality of the blade members are provided so as to stand and are arranged with intervals in a circumferential direction on a face portion of the shroud, the face portion facing the base plate. A plurality of groove portions for mounting each of a plurality of the blade members are formed on the base plate, and a plurality of the groove portions are configured so as to mount each of the blade members included in a plurality of kinds of the shrouds in which at least one of an arrangement of the blade members and a number of the blade members is different from each other.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and additional features and characteristics of this disclosure will become more apparent from the following detailed description considered with the reference to the accompanying drawings.

FIG. 1 is a perspective view of a rotor mounting an impeller.

FIG. 2 is a vertically cross-sectional view of the rotor mounting the impeller.

FIG. 3 is a explored perspective view of the impeller.

FIG. 4 is a plan view of a shroud.

FIG. 5 is a bottom view of the shroud.

FIG. 6 is a bottom-side perspective view of the shroud.

FIG. 7 is a plan view of an end portion of the rotor (a base plate).

FIG. 8 is a plan view of a base plate in an impeller of a second embodiment.

FIG. 9 is a plan view illustrating a modification example of a base plate of the second embodiment.

FIG. 10 is a plan view of a base plate in an impeller of a third embodiment.

DETAILED DESCRIPTION

Hereinafter, embodiments disclosed herein will be explained with reference to the drawings.

FIGS. 1 to 3 illustrate a rotor unit A of an inner rotor type brushless motor for use in a vehicle-mounted water pump. The rotor unit A is constituted of a rotor 1 for the brushless motor and an impeller 2. A magnet 3 is insertion-molded in the rotor 1. The impeller 2 includes a base plate 11 disposed at one end side of the rotor 1, and a shroud 21 joined to the base plate 11. The base plate 11 is disposed at one end side of the rotor 1 through a joint shaft portion 4, and is formed in a circular shape around a rotation axis X. The rotor 1 including the base plate 11 and the joint shaft portion 4 is integrally molded by using a resin material.

As illustrated in FIG. 2, a rotation shaft insertion hole 5 penetrating from the rotor 1 to the base plate 11 through the joint shaft portion 4 is formed in a central portion of the rotor unit A. A bush 6 is disposed in the rotation shaft insertion hole 5 by means of a method such as press fitting and adhesive bonding, and a shaft (not illustrated) is inserted on an inner circumferential face of the bush 6 from the side of the impeller 2.

As illustrated in FIGS. 3 to 6, the shroud 21 is concentrically provided with a cylindrical portion 23 forming a suction inlet 22, and a circular flange portion 24. A plurality of (seven in the present embodiment) blade members 25 are disposed across from an inner circumferential face 23 a of the cylindrical portion 23 to a back face 24 a of the circular flange portion 24. A plurality of the blade members 25 are provided so as to stand and are arranged with fixed intervals in a circumferential direction along a curved shape on the inner circumferential face 23 a and the back face 24 a (an example of a face portion facing the base plate 11).

As illustrated in FIGS. 5 and 6, each of a plurality of the blade members 25 includes, on an end portion at a side facing the base plate 11, an insertion piece 25 a having a rectangular cross section and being formed to protrude from the blade member 25. Note that, in FIG. 6, among seven blade members 25 included in the shroud 21, only four blade members 25 are illustrated, and three blade members 25 are omitted. Further, as illustrated in FIGS. 3 and 7, the base plate 11 is formed with a plurality of groove portions 12 being rectangular concave portions for use in mounting the blade members 25 by inserting a plurality of the insertion pieces 25 a. The shroud 21 is fixed to the base plate 11 by welding the groove portions 12 with the insertion pieces 25 a of a plurality of the blade members 25 by means of, for example, ultrasonic welding. Note that the method of fixing the blade members 25 to the base plate 11 is not limited to the ultrasonic welding, but may be vibration welding, thermal welding, or the like.

A plurality of the groove portions 12 are formed so as to be capable of mounting respective blade members 25 included in each of a plurality of kinds of the shrouds 21 in which at least one of an arrangement of the blade members 25 and the number of the blade members 25 is different from each other. As illustrated in FIG. 7, the groove portions 12 whose number (fourteen in the present embodiment) is twice the number (seven in the present embodiment) of the blade members 25 disposed in the shroud 21 are formed on the base plate 11.

In the present embodiment, the base plate 11 includes, as a plurality of (fourteen) groove portions 12, seven first groove portions 13 associated with one of two kinds of the shrouds 21 in which arrangements of the blade members 25 are different from each other, and seven second groove portions 14 associated with the other one of the two kinds of the shrouds 21. When the blade members 25 applying centrifugal force to fluid in conjunction with a rotation of the base plate 11 in one direction (for example, a direction S1 in FIG. 7) is defined as first blade members, and the blade members 25 applying centrifugal force to the fluid in conjunction with a rotation of the base plate 11 in a direction (for example, a direction S2 in FIG. 7) opposite to the one direction is defined as second blade members, the base plate 11 is configured to mount each of the first groove portions and the second groove portions by a plurality of the groove portions 12. Specifically, among a plurality of the groove portions 12, the first groove portions 13 are formed so as to mount the first blade members, and the second groove portions 14 are formed so as to mount the second blade members. In the present embodiment, the first groove portions 13 and the second groove portions 14 are formed as independent grooves without intersecting with each other on the base plate 11.

On a part of a plurality of the first groove portions 13 and a part of a plurality of the second groove portions 14, convex portions 13 a and 14 a are formed in a longitudinal direction, two faces of the convex portions opposite to each other being separated from each other. The convex portions 13 a and 14 a have the same protrusion amount. According to the convex portions 13 a and 14 a, insertion pieces 25 a of the blade members 25 are press-fit into the first groove portions 13 and the second groove portions 14. With this configuration, a position of the shroud 21 relative to the base plate 11 is fixed, and even when the blade members 25 are ultrasonically welded with the base plate 11, an axis of the blade members 25 is prevented from displacement. Further, when the impeller 2 is rotated, the blade members 25 come into contact with the convex portions 13 a and 14 a, and thereby, movement of the blade members 25 relative to the base plate 11 in a direction of rotation is prevented.

Note that the groove portions 13 and 14 provided with the convex portions 13 a and 14 a are not limited to a part of the groove portions 13 and 14, but all the groove portions 13 and 14 may be provided with the convex portions 13 a and 14 a. The groove portions 13 and 14 may not be provided with the convex portions 13 a and 14 a when the groove portions 13 and 14 are formed with a size being substantially the same as a size of the insertion pieces 25 a of the blade members 25.

In this way, a plurality of the groove portions 12 of the base plate 11 are formed at positions associated with the blade members 25 included in a plurality of kinds of the shrouds 21 in which at least one of an arrangement of the blade members 25 and the number of the blade members 25 is different from each other. This configuration enables a plurality of kinds of the shrouds 21 each including the blade members 25 with a different arrangement to be mounted on a single base plate 11. Further, the base plate 11 can be shared by the blade members 25 in which at least one of an arrangement and the number of the blade members is different from each other, and thus, a manufacturing cost of the impeller 2 can be reduced,

Second Embodiment

In the first embodiment, there has been described an example in which each of the first groove portions 13 and each of the second groove portions 14 are independently formed without intersecting with each other. In contrast to this configuration, in the present embodiment, as illustrated in FIG. 8, each of the first groove portions 13 and each of the second groove portions 14 are formed with intersecting with each other. Note that the other configurations are the same as those of the first embodiment.

Intersecting each of the first groove portions 13 and each of the second groove portions 14 with each other enables narrowing of a region occupied by one groove portion 12 on the base plate 11. This allows a large number of groove portions 12 to be arranged on the base plate 11, thereby enabling the base plate 11 to be associated with a plurality of kinds of the shrouds 21.

Modification Example of Second Embodiment

As illustrated in FIG. 9, the first groove portions 13 and the second groove portions 14 formed on the base plate 11 may be formed in such a way that, in intersecting groove portions, depths of grooves are different from each other. In FIG. 9, in the first groove portions 13 and the second groove portions 14, deep groove portions are illustrated by solid lines, and shallow groove portions are illustrated by dashed lines. In the present modification example, in a circumferential direction of the base plate 11, the first groove portions 13 and the second groove portions 14 are each formed in such a way that deep groove portions and shallow groove portions are nearly alternately arranged. Although not illustrated, a plurality of the groove portions 12 may be configured in such a way that one set of groove portions (for example, the first groove portions 13) among a set of the first groove portions 13 and a set of the second groove portions 14 are made deep, and the other set of groove portions (for example, the second groove portions 14) are made shallow.

Third Embodiment

In the present embodiment, as illustrated in FIG. 10, first groove portions 13 and second groove portions 14 are alternately arranged in the circumferential direction of the base plate 11, and the first groove portions 13 and the second groove portions 14 are inclined toward the same direction. In this regard, however, when a straight line extending outward from a rotation axis X (an example of a center of the base plate 11) in a radial direction of the base plate 11 is defined as a reference line L, inclination angles of each first groove portion 13 and each second groove portion 14 relative to the reference line L are different from each other. In an example illustrated in FIG. 10, an inclination angle of each first groove portion 13 relative to a reference line L1 is denoted by θ1, an inclination angle of each second groove portion 14 relative to a reference line L2 is denoted by θ2, and θ1 is larger than θ2. Forming the first groove portions 13 and the second groove portions 14 on the base plate 11 in this way enables the base plate 11 of the impeller 2 to be associated with two kinds of the shrouds 21 including the blade members 25 applying centrifugal force, in the same direction, to fluid in conjunction with rotation of the base plate 11, and having a different arrangement.

Other Embodiments

In the above embodiments, there has been described an example in which the shroud 21 includes seven blade members 25 and seven groove portions 12 associated with the blade members 25, respectively, are provided on the base plate 11, but the number of the blade members 25 included in the shroud 21 may be smaller than or equal to six or larger than or equal to eight, and it is sufficient that the number of the groove portions 12 is associated with the number of the blade members 25 included in the shroud 21.

A plurality of the groove portions 12 formed on the base plate 11 may be configured in such a way that the number of the first groove portions 13 is different from the number of the second groove portions 14. This configuration enables a plurality of the groove portions 12 to be associated with a plurality of the shrouds 21 in which there is a difference in the number of the blade members 25.

In the above third embodiment, there has been described an example in which, on the base plate 11 of the impeller 2 which is rotated counterclockwise (the direction S1 in FIG. 10) when seen from the side of the shroud 21, a set of the first groove portions 13 and a set of the second groove portions 14 are formed so as to be respectively associated with a plurality of kinds of the shrouds 21 each including the blade members 25 with one of inclination angles (θ1 and θ2) different from each other. Instead of this configuration, on the base plate 11 of the impeller 2 which is rotated clockwise (the direction 52 in FIG. 10) when seen from the side of the shroud 21, the set of the first groove portions 13 and the set of the second groove portions 14 may be formed so as to be respectively associated with a plurality of kinds of the shrouds 21 each including the blade members 25 with one of inclination angles (θ1 and θ2) different from each other.

On the base plate 11, there may be formed a plurality of groove portions 12 that are associated with three or more kinds of the shrouds 21 each including the blade members 25 in which at least one of an arrangement and the number of the blade members 25 is different from each other.

An impeller in the above-described embodiments, as an example, includes a base plate, and a shroud including a plurality of blade members fixed to the base plate. A plurality of the blade members are provided so as to stand and are arranged with intervals in a circumferential direction on a face portion of the shroud, the face portion facing the base plate. A plurality of groove portions for mounting each of a plurality of the blade members are formed on the base plate, and a plurality of the groove portions are configured so as to mount each of the blade members included in a plurality of kinds of the shrouds in which at least one of an arrangement of the blade members and a number of the blade members is different from each other.

This configuration enables a plurality of kinds of the shrouds including blade members in which at least one of an arrangement and the number of the blade members is different from each other to be mounted on a single base plate. Further, the above configuration enables a plurality of kinds of the shrouds to share the base plate, and thus, a manufacturing cost of the impeller can be reduced.

In the impeller in the above-described embodiments, as an example, the base plate includes, as a plurality of the groove portions, first groove portions and second groove portions respectively associated with two kinds of the shrouds in which arrangements of the blade members are different from each other. When blade members applying centrifugal force to fluid in conjunction with a rotation of the base plate in one direction are defined as first blade members, and blade members applying centrifugal force to fluid in conjunction with a rotation of the base plate in a direction opposite to the one direction are defined as second blade members, the first groove portions are formed at positions to mount each of the first blade members, and the second groove portions are formed at positions to mount each of the second blade members.

Accordingly, when mounting, onto the base plate, two kinds of the shrouds including blade members in which there is a difference in a direction of the blade members that applies centrifugal force to fluid by being rotated, the impeller can be constituted by mounting the blade members into the first groove portions or the second groove portions, in other words, two kinds of impellers respectively including two sets of blade members, rotation directions of which are different from each other, can be mounted and provided on a single base plate. With this configuration, impellers, rotation directions of which are different from each other at the time of applying centrifugal force to fluid, can be manufactured at low cost.

In the impeller in the above-described embodiments, as an example, the base plate includes, as a plurality of the groove portions, first groove portions and second groove portions respectively associated with two kinds of the shrouds in which arrangements of the blade members are different from each other, and inclination angles of the first groove portions and the second groove portions relative to a reference line are different from each other, the reference line being a straight line extending outward from a center of the base plate in a radial direction.

Accordingly, when mounting, onto the base plate, two kinds of the shrouds including blade members each inclination direction of which relative to a reference line extending outward from a rotation axis in a radial direction is the same and an arrangement of which are different from each other, the impeller can be constituted by mounting the blade members into the first groove portions or the second groove portions. In other words, two kinds of impellers including blade members each rotation direction of which is the same and inclination angles of which are different can be mounted onto a single base plate. With this configuration, impellers with the same number of rotations and a different discharge flow rate for fluid can be manufactured at low cost.

In the impeller in the above-described embodiments, as an example, each of the first groove portions and each of the second groove portions are independently formed without intersecting with each other,

Accordingly, the first groove portions and the second groove portions can be clearly distinguished on the base plate. This facilitates alignment between the blade members of the shroud and the groove portions of the base plate at the time of mounting.

In the impeller in the above-described embodiments, as an example, each of the first groove portions and each of the second groove portions are formed with intersecting with each other.

Accordingly, a region occupied by a plurality of the groove portions are narrowed on the base plate. This increases a degree of freedom in arrangement of a plurality of kinds of groove portions, as compared with a case in which the groove portions do not intersect with each other.

The principles, preferred embodiment and mode of operation of the present invention have been described in the foregoing specification. However, the invention which is intended to be protected is not to be construed as limited to the particular embodiments disclosed. Further, the embodiments described herein are to be regarded as illustrative rather than restrictive. Variations and changes may be made by others, and equivalents employed, without departing from the spirit of the present invention. Accordingly, it is expressly intended that all such variations, changes and equivalents which fall within the spirit and scope of the present invention as defined in the claims, be embraced thereby. 

1. An impeller comprising: a base plate; and a shroud including a plurality of blade members fixed to the base plate, wherein a plurality of the blade members are provided so as to stand and are arranged with intervals in a circumferential direction on a face portion of the shroud, the face portion facing the base plate, a plurality of groove portions for mounting each of a plurality of the blade members are formed on the base plate, and a plurality of the groove portions are formed so that each of the blade members of a plurality of kinds of the shrouds different in at least one of arrangement and number of the blade members can be mounted.
 2. The impeller according to claim 1, wherein the base plate includes, as a plurality of the groove portions, first groove portions and second groove portions respectively associated with two kinds of the shrouds in which arrangements of the blade members are different from each other, and, when blade members applying centrifugal force to fluid in conjunction with a rotation of the base plate in one direction are defined as first blade members, and blade members applying centrifugal force to fluid in conjunction with a rotation of the base plate in a direction opposite to the one direction are defined as second blade members, the first groove portions are formed at positions to mount each of the first blade members, and the second groove portions are formed at positions to mount each of the second blade members.
 3. The impeller according to claim 1, wherein the base plate includes, as a plurality of the groove portions, first groove portions and second groove portions respectively associated with two kinds of the shrouds in which arrangements of the blade members are different from each other, and inclination angles of the first groove portions and the second groove portions relative to a reference line are different from each other, the reference line being a straight line extending outward from a center of the base plate in a radial direction.
 4. The impeller according to claim 2, wherein each of the first groove portions and each of the second groove portions are independently formed without intersecting with each other.
 5. The impeller according to claim 2, wherein each of the first groove portions and each of the second groove portions are formed with intersecting with each other.
 6. The impeller according to claim 3, wherein each of the first groove portions and each of he second groove portions are independently formed without intersecting with each other.
 7. The impeller according to claim 3, wherein each of the first groove portions and each of the second groove portions are formed with intersecting with each other. 